Sole component for an article of footwear and method for making same

ABSTRACT

A sole component having a base, a toe cover and an integral line of articulation permitting the toe cover to be molded in an “open” position and moved into a “closed” position during assembly on the article of footwear. The line of articulation may include a line of reduced thickness extending laterally across the sole. The line of articulation may also include breaks defined in the sidewall of the sole in alignment with the line of reduced thickness. The present invention also provides a method of forming a sole component generally including the steps of providing a mold having bottom and top mold parts shaped to cooperatively define a mold cavity in the shape of a sole component having a toe cover joined to a base along a line of articulation, closing the mold parts, injecting a sole forming material into the cavity, removing the sole component and moving the toe cover about the line of articulation into a closed configuration for use.

BACKGROUND OF THE INVENTION

The present invention relates to a sole component for an article offootwear and a method for making the sole component.

There is an ongoing effort in the footwear industry to produce footwearthat provides durability and a high level of comfort, while maintaininga sense of style. As the styles change, so must the methods ofmanufacturing the shoes. However, such changes can and often do resultin manufacturing difficulties.

Many of today's shoes include either a partial or complete toe cover,such that the toe of the shoe in encompassed at least partially by solematerial. The primary difficulty with toe cover constructions is how thetoe cover can be formed and attached via machinery. For example, in oneconstruction the toe cover is formed as an integral part of the outsole.In this construction, the outsole extends the full length of the shoeand includes a heel cup at the rear of the shoe and a toe cover at thefront of the shoe. Given the undercut nature of the toe cover, this solecannot be manufactured using a conventional mold with a single movingmold part because the toe cover would entrap a portion of the moldpreventing its removal from the mold.

A number of efforts have been made to improve on the conventionalconstruction described above. In another conventional construction, aclog is provided with a molded midsole and an outsole attached to themidsole. In this construction, the toe cover is integrated into themidsole, rather than the outsole. The midsole is manufactured in asingle molding step from lightweight elastomeric material, which ispliable, flexible and easily removed from the molding equipment. Theoutsole is made of multiple parts that are affixed to the midsole. Theparts of the outsole may be formed of harder materials in the areas ofgreatest wear.

In yet another construction, both the sole and midsole are provided withtoe covers. In this construction, the outsole is manufactured using arelatively complex multi-part mold. This permits the outsole to beremoved from the mold in a direction substantially parallel to the planeof the outsole. The midsole is formed from multiple sections that arefitted into the outsole and affixed to one another. The use of multiplemidsole sections may avoid the need for complex multi-part moldingequipment for the midsole. Once assembled, the outsole hides the seamwhere the midsole sections are affixed to one another.

SUMMARY OF THE INVENTION

The present invention provides a sole component having a toe cover and aline of articulation that permits the outsole to be molded in an openconfiguration and moved into a closed configuration during assembly onthe article of footwear. In one embodiment, the line of articulation isa line of reduced material thickness extending across the width of thesole. In one embodiment, the sole component includes a sidewall and theline of articulation includes at least one break defined in thesidewall. In one embodiment, the sole component is an outsole.

The present invention also provides a method of forming an articulatingsole component with a toe cover. The method includes providing a moldhaving bottom and top mold parts for forming a sole with a toe cover inan open configuration. The bottom and top mold parts are closed tocooperatively define a cavity. The mold parts are contoured to define amold cavity that will provide the molded sole component with a line ofarticulation adjacent the toe cover. The line of articulation permitsthe toe cover to be moved into a closed position after molding. A solematerial is injected into the cavity for forming the sole component.Once sufficiently cured, the sole component is removed from the mold inthe open configuration. During assembly to the article of footwear, thetoe cover is pivoted into the closed position about the liner ofarticulation to provide the finished article of footwear with a closedtoe cover. In one embodiment, the sole component is an outsole and theoutsole is secured to the article of footwear by cement or otheradhesives. In one embodiment, the article of footwear includes aremovable footbed and the outsole with articulating toe cover is secureddirectly to the undersurface of the upper with the toe cover covering atleast a portion of the toe region of the upper. In one embodiment, thesole includes a midsole secured to the undersurface of the upper and thearticulating outsole is secured to the midsole with toe cover extendingabove the midsole covering at least a portion of the toe region of theupper.

The present invention provides a sole component with a toe cover thatcan be easily manufactured using a conventional mold with only a singlemoving mold part. The sole includes a line of articulation that permitsthe toe cover to be easily articulated between open and closedpositions. The sole component of the present invention can be used withany footwear and enables a toe cover to be formed as a single unit withthe outsole. The present invention also provides a method formanufacturing a sole component with a toe cover that can be implementedusing a conventional mold with only a single moving part. The presentinvention provides an article of footwear that provides a desiredaesthetic appeal while reducing the costs associated with themanufacture of conventional constructions of similar design.

These and other objects, advantages, and features of the invention willbe readily understood and appreciated by reference to the detaileddescription of the current embodiment and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of the articulating outsole of the presentinvention

FIG. 2 is a side view of a boot incorporating the articulating sole ofthe present invention;

FIG. 3 bottom view of the articulating outsole of the present invention;

FIG. 4 is a medial view of the articulating outsole of the presentinvention;

FIGS. 5A and 5B are side views of a side views of a standard molds,depicting the problems with forming an outsole having a toe coverincorporated therein; and

FIGS. 6A and 6B are side views of the molds of the present invention.

DESCRIPTION OF THE CURRENT EMBODIMENT

An article of footwear incorporating an outsole manufactured inaccordance with an embodiment of the present invention is shown in FIG.2. For purposes of disclosure, the present invention is described inconnection with boot 100. The outsole of this embodiment is shown inFIG. 1 and generally designated 10. In the illustrated embodiment, theoutsole 10 is incorporated into a boot 100 that includes an upper, aninternal midsole 14 (or footbed), and an outsole 10. The outsole 10 isan articulating sole and is described in more detail below. The outsole10 includes a toe cover 30 and a line of articulation 36 that permitsthe toe cover 30 to be molded in an open position (See FIG. 1B) andmoved into a closed position (See FIG. 1A) after molding, for example,during assembly on the boot 100. The present invention is, however, wellsuited for us in other types of footwear, including other outdoorfootwear, walking footwear, athletic footwear, multisport footwear, andwork footwear. The invention is equally well suited for use inconnection with other types of footwear including shoes, sandals, andother soled footwear. Accordingly, the terms “boot” and “shoe” are usedinterchangeably in this disclosure to refer to soled footwear ingeneral.

As noted above, boot 100 includes an upper 12, an internal midsole 14and an outsole 10. The upper 12 is manufactured from conventionalmaterials (e.g. leather or other sufficiently durable material)according to conventional methods. For example, the upper 12 may utilizea conventional stroble construction. In the illustrated embodiment, theupper 12 is configured (e.g. sized and shaped) to accommodate aninternal midsole 14 and, optionally, an internal insole (not shown) orsockliner (not shown). Alternatively, the upper 12 may be manufacturedfor use with an external midsole (i.e. a midsole disposed outside of andbeneath the upper) (not shown). The outsole 10 is secured to the upper12 using a cement or adhesive construction. Although described inconnection with a cemented construction having an internal midsole, thepresent invention is well-suited for use in connection with essentiallyany footwear construction where a toe cover is desired. For example, thestyle of the upper 12, the sole configuration and the manner of securingthe outsole 10 to the boot 100 may vary depending on the design of thearticle of footwear.

The outsole 10 is manufactured from essentially any material suitablefor providing a durable and non-slip wear surface. The design andconfiguration of the outsole 10 will vary from application toapplication as desired. In the illustrated embodiment, the outsole 10 isa polymeric material selected from one of many well-known outsolematerials having relatively high durometer, such as natural or syntheticrubber. The outsole 10 includes an upper surface 18 that is secured tothe lower surface of the upper 12, for example, by cement or otheradhesives. The outsole 10 also includes a lower surface 22 that isshaped to define the desired tread pattern. For example, the lowersurface 22 can include a plurality of cleats 24 or other tread elements.In the illustrated embodiment, the outsole 10 is a cup-sole in the sensethat it generally includes a base 60 and a sidewall 62. The base 60 ofthis embodiment generally forms the bottom of the outsole 10 beingsubstantially coextensive with the bottom of the upper 12. The sidewall62 extends upwardly around the periphery of the base 60 such that thebase 60 and sidewall 62 cooperatively define a cup-shaped seat for thebottom of the upper 12.

The outsole 10 of the illustrated embodiment generally includes aforefoot portion 26 and a heel portion 34. The forefoot portion 26extends through the forefoot region 28 of the outsole 10, providing awear surface that engages the ground beneath the forefoot of thewearer's foot. In the illustrated embodiment, the bottom surface of theforefoot portion 26 is textured to provide improved traction. Ifdesired, the forefoot portion 26 can include tread, lugs or othertraction improving elements. The forefoot portion 26 is shaped toinclude a toe cover 30. The toe cover 30 extends from the forefootportion 26 above and over the upper 12. In the illustrated embodiment,the toe cover 30 is an extension of the sidewall 62. The toe cover 30provides additional structural support for the upper 12 as well asprotecting the toe region of the boot 100 and the toes of the individualwearing the boot 100. In the illustrated embodiment, the heel portion 34extends past the heel region 32 of the outsole 10, providing a wearsurface that engages the ground beneath the heel of the wearer's footand extends upward, covering a portion of the upper 12 located at theback of the boot 100. The bottom surface of the illustrated heel portion34 is textured to provide improved traction. Like the forefoot portion24, the heel portion 34 can include treads, lugs or other tractionimproving elements, as desired. In the illustrated embodiment, theforefoot portion 26 and heel portion 34 are molded as a single unit andsecured by cement or other conventional adhesives.

The outsole 10 also includes a line of articulation or articulatingjoint 36 located in the forefoot portion 26. In the illustratedembodiment, the articulating joint 36 includes a line of reducedthickness 66 extending laterally across the base 60 of the outsole 10.The thickness of the material through the line of reduced thickness 66may vary from application to application as desired to provide a highlyflexible articulating joint 36. If desired, the cross-sectional shape ofthe material through the line of reduced thickness 66 may be selected toenhance flexibility. For example, the line of reduced thickness 66 mayinclude an arched or bowed shape that easily bends through the desiredrange of motion of the toe cover 30. Additionally, the illustratedarticulating joint 36 includes breaks 64 in the sidewall 62 that aresubstantially aligned with opposite ends of the line of reducedthickness 66. As shown, the breaks 64 in the illustrated outsole 10 canbe integrated into the design of the sidewall 62 to provide anaesthetically pleasing appearance. The breaks 64 may, however, haveessentially any alternative configuration that provides the line ofarticulation with the desired flexibility. For example, the breaks 64may be thin cuts or slits through the sidewall 62. Cooperatively, theline of reduced thickness 66 and the breaks 64 in the sidewall 62provide a living hinge that permits the toe cover 30 to pivot withrespect to the remainder of the outsole 10. The articulating joint 36may have alternative configurations in different applications. Forexample, the articulating joint 36 made include a channel (continuous ordiscontinuous), hinge, groove, perforations or other similar pivotabledevice that can be formed as one with the outsole 10.

As noted above, the articulating joint 36 enables the outsole 10 to beformed as a single unit in the mold despite the presence of the toecover 30. The joint or hinge 36, as shown in FIGS. 6A and 6B, allows theoutsole 10 to be formed in an “open” configuration and easily moved intoa “closed” position after molding. In other words, the articulatingjoint 36 permits the toe cover 30 to be formed in an orientation thatdoes not create an undercut region in the mold. This allows the outsole10 to be removed from the mold without the need for complex multi-partmolds. Once the outsole 10 is removed from the mold, the articulatingjoint 36 permits the toe cover 30 to be pivoted into the appropriate“closed” configuration. For example, during assembly of the boot 100,the toe cover 30 can be pivoted up over the upper 12 and secured toprovide a permanent cover over a portion of the toe.

Manufacture of boot 100 will now be described with reference to FIGS. 5and 6. The upper 12 is generally conventional and will not therefore bedescribed in detail. Suffice it to say that upper is manufactured fromconventional upper materials using conventional techniques andapparatus. In the illustrated embodiment, the bottom of the upper isclosed, for example, by a stroble construction or any other suitableconstruction. The closed upper 12 may be secured to the outsole 10 usingconventional adhesives.

The boot 100 includes a removable midsole 14 (or footbed) that functionsto provide the desired cushioning. The midsole 14 is manufactured froman appropriate cushioning material, such as PU or EVA. The firmness ofthe midsole 14 may vary from application to application as desired. Themidsole 14 may be manufactured using conventional techniques andapparatus. For example, the midsole 14 may be compression molded, pourmolded, injection molded and die cut from a sheet stock. The midsole 14may be manufactured using other techniques and apparatus correspondingto the selected insole material. The manufactured midsole 14 isremovably fitted into the upper 12 to overlie the bottom of the upper 12and provide a comfortable cushioning bed for the wearer's foot.Alternatively, the midsole 14 could be secured to the bottom of theupper using conventional cements or other adhesives.

In the illustrated embodiment, the outsole 10 may be manufactured usinga generally conventional mold having a single linearly moving mold part.The molds used for manufacturing the illustrated outsole 10 are shown inFIGS. 6A and 6B. As shown, in the illustrated embodiment, the outsole 10is injection molded using generally conventional injection moldingmachinery. The outsole 10 is molded from material having the desiredresiliency and wear characteristics, such as a relatively high durometerpolyurethane material. As shown in FIG. 6, the mold includes two parts,a bottom part 38 and a top part 40. The mold parts 38 and 40 areconfigured to cooperatively define a mold cavity 70 that forms theoutsole 10 with the toe cover 30 in an “open” configuration. In otherwords, the outsole 10 is formed with the toe cover 30 in a rotatedposition that opens in the same as the motion of the mold parts so thatthe toe cover 30 does not create an undercut that is of sufficient depthto prevent operation of the molds. As a result, the outsole 10 producedvia the mold can easily be released from the mold and can be formedusing only the bottom part 38 and top part 40.

The outsole 10 is preferably attached to the midsole part 16 usingconventional techniques and apparatus. In the illustrated embodiment,the outsole 10 is secured to the lower surface of the upper 12 by cementor other adhesives.

The sole construction may also include an insole (not shown) orsockliner (not shown) fitted into the upper 12 above the midsole 14. Ifincluded, the insole or sockliner may be manufactured using conventionaltechniques and apparatus. The insole or sockliner may be removablypositioned over the midsole 14 or secured to the upper surface of themidsole 14, as desired.

The above description is that of the current embodiment of theinvention. Various alterations and changes can be made without departingfrom the spirit and broader aspects of the invention as defined in theappended claims, which are to be interpreted in accordance with theprinciples of patent law including the doctrine of equivalents. Anyreference to claim elements in the singular, for example, using thearticles “a,” “an,” “the” or “said,” is not to be construed as limitingthe element to the singular.

1. A method of forming a sole component for footwear, comprising;providing a mold having bottom and top mold parts, the mold parts shapedto define a mold cavity in the form of a sole component having a base, atoe cover in an open configuration, and an articulation joint adjacentthe toe cover; closing the bottom and top mold parts to cooperativelydefine the cavity; injecting a sole forming material into the cavity forforming the sole component; removing the formed sole component from themold in the open configuration; and moving the toe cover about the lineof articulation into a closed configuration.
 2. The method of claim 1,wherein the formed sole component is made of a durable material.
 3. Themethod of claim 1, wherein said injecting step further includes coolingthe sole component prior to removal from the mold.
 4. The method ofclaim 1, wherein said removing step further includes moving at least oneof the top mold part and the bottom mold part to provide access to thesole component prior to removing the sole component from the mold.
 5. Anarticulating sole component formed according to the method set forth inclaim
 1. 6. The articulating sole component of claim 5, wherein saidsole component is further defined as an outsole, said outsole formed ofa durable wear-resistant material.
 7. The articulating sole component ofclaim 6, wherein said outsole further includes a sidewall.
 8. Thearticulating sole component of claim 7, wherein said articulation jointincludes at least one break defined in said sidewall.
 9. Thearticulating sole component of claim 8, wherein said articulation jointincludes a line of reduced thickness.
 10. An article of footwearincorporating the articulating sole component of claim
 6. 11. An articleof footwear incorporating the articulating sole component of claim 7.12. An article of footwear incorporating the articulating sole componentof claim
 8. 13. The article of footwear of claim 12 further comprisingan upper with a bottom and a toe region, said outsole secured to saidbottom of said upper with said toe cover covering at least a portion ofsaid toe region.
 14. A sole component for an article of footwearcomprising: a base; a toe cover integral with said base, said toe coverextending from said base; and an articulation joint disposed adjacent tosaid toe cover, said toe cover being pivotally movable about saidarticulation joint between an open position and a closed position. 15.The sole component of claim 14 wherein said articulation joint includesa line of reduced thickness extending at least partially across saidbase.
 16. The sole component of claim 15 further including a sidewallextending upwardly form said base along at least a portion of aperiphery of said base, said sidewall defining a break, said break beingsubstantially aligned with said line of reduced thickness.
 17. The solecomponent of claim 14 further including a sidewall extending upwardlyform said base along at least a portion of a periphery of said base,said articulation joint including at least one break defined in saidsidewall.
 18. The sole component of claim 15 wherein said sole componentis further defined as an outsole, said outsole being formed of a durablematerial.
 19. An article of footwear comprising: an upper having abottom and defining and internal space, said upper including a toeregion; an outsole secured to said bottom of said upper, said outsoleincluding a base and a toe cover, said toe cover covering at least aportion of said toe region of said upper, said outsole further includinga line of articulation adjacent said toe cover for pivotally moving saidtoe cover with respect to said base between open and closed positions,whereby said outsole may be formed with said toe cover in an openposition in which said toe cover does not define an undercut regionwithin a mold cavity and, after forming, said toe cover may be movedinto a closed position in which said toe cover covers said toe region insuch a way that said toe cover would have created an undercut region inthe mold had said outsole been formed with said toe cover in said closedposition.
 20. The article of footwear of claim 19 wherein said outsoleincludes a sidewall extending upwardly from at least a portion of saidbase, said line of articulation including at least one break in saidsidewall.
 21. The article of footwear of claim 19 wherein said line ofarticulation include a line of reduced thickness extending at leastpartially across said outsole.
 22. The article of footwear of claim 19wherein said line of articulation include a line of reduced thicknessextending at least partially across said outsole; and wherein saidoutsole includes a sidewall extending upwardly from at least a portionof said base, said line of articulation including at least one break insaid sidewall, said break being in substantial alignment with said lineof articulation.